I have the same issue on Radeon 570 4gb, Ryzen 1700, MSI Tomahawk on 18.04.
The only way to boot is to use IOMMU=soft. -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux in Ubuntu. https://bugs.launchpad.net/bugs/1747463 Title: kernel crashes during boot unless IOMMU is disabled on Ryzen 1800X Status in Linux: Confirmed Status in linux package in Ubuntu: Confirmed Status in linux source package in Bionic: Confirmed Status in linux source package in Cosmic: Confirmed Bug description: I'm on a Ryzen 1800X and Biostar B350GT5 on bionic kubuntu. There are lots of AMD-Vi logged events and I get irq crashes or acpi hangups with a 'normal' boot. I got it to boot by disabling IOMMU in the BIOS and adding "iommu=soft" to the kernel booting options in grub. linux can then detect everything properly (all cores) and I've had zero crashes. The only issue is that it's using software IOMMU which could have a performance penalty because it has to copy all the data of some PCI devices to sub 4G regions. Alternatively it boots with the kernel option "acpi=off" but only detects a single core/thread. I attached a kernel log. I believe(d) this might be related to https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1671360 and https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1690085 --- ApportVersion: 2.20.8-0ubuntu8 Architecture: amd64 AudioDevicesInUse: USER PID ACCESS COMMAND /dev/snd/controlC1: fixme 1487 F.... pulseaudio /dev/snd/controlC0: fixme 1487 F.... pulseaudio CurrentDesktop: KDE DistroRelease: Ubuntu 18.04 HibernationDevice: RESUME=UUID=bc971fcc-8e63-4fa5-a149-af4af6c8eece InstallationDate: Installed on 2018-01-31 (4 days ago) InstallationMedia: Kubuntu 18.04 LTS "Bionic Beaver" - Alpha amd64 (20180131) IwConfig: lo no wireless extensions. enp3s0 no wireless extensions. MachineType: BIOSTAR Group B350GT5 Package: linux (not installed) ProcFB: 0 amdgpudrmfb ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-4.13.0-32-generic.efi.signed root=/dev/mapper/kubuntu--vg-root ro iommu=soft quiet splash vt.handoff=1 ProcVersionSignature: Ubuntu 4.13.0-32.35-generic 4.13.13 RelatedPackageVersions: linux-restricted-modules-4.13.0-32-generic N/A linux-backports-modules-4.13.0-32-generic N/A linux-firmware 1.170 RfKill: Tags: bionic Uname: Linux 4.13.0-32-generic x86_64 UpgradeStatus: No upgrade log present (probably fresh install) UserGroups: adm cdrom dip lpadmin plugdev sambashare sudo _MarkForUpload: True dmi.bios.date: 11/30/2017 dmi.bios.vendor: American Megatrends Inc. dmi.bios.version: 5.13 dmi.board.asset.tag: None dmi.board.name: B350GT5 dmi.board.vendor: BIOSTAR Group dmi.chassis.asset.tag: Default string dmi.chassis.type: 3 dmi.chassis.vendor: Default string dmi.chassis.version: Default string dmi.modalias: dmi:bvnAmericanMegatrendsInc.:bvr5.13:bd11/30/2017:svnBIOSTARGroup:pnB350GT5:pvr:rvnBIOSTARGroup:rnB350GT5:rvr:cvnDefaultstring:ct3:cvrDefaultstring: dmi.product.family: None dmi.product.name: B350GT5 dmi.sys.vendor: BIOSTAR Group To manage notifications about this bug go to: https://bugs.launchpad.net/linux/+bug/1747463/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp
